I’ll add more modifiers as I go, but usually I’d just use a spline with two control points. If you set the curvature to 0, you’ll get a straight linear falloff between them.
Btw, I've just learned that the correct name for the "cone" modifier on a cuboid is "quadrilateral frustrum apex truncatred square pyramid" (or perhaps "taper" or "draft" if one wants to use what we do in the CAD world). :D
